The present invention relates to an optical disk, an optical disk reproducing device and an optical disk reproduction system which allow only part of recorded information to be selectively reproduced from the optical disk depending on the type of the reproducing device employed.
For game software recorded in a CD-ROM, it is sometimes desire that the stored game software be able to be reproduced only via a dedicated game machine rather than non-dedicated or ordinary CD-ROM players. Further, for a plurality of pieces of information recorded on an optical disk, one may desire that only some of the stored pieces of information to able to be selectively reproduced from the optical disk depending on the type of a disk player used. However, there have heretofore been no optical disk and optical disk reproducing device that satisfy such demands.